Field of the Invention
The invention relates to spiral binder applying machines such as those such as that disclosed in Ostermeier, U.S. Pat. No. RE 26,929 issued June 30, 1970. Such machines are used to insert spiral binders in perforated packs of sheets, and include front and rear clamps having facing surfaces between which the spine of the unbound pack is held. A coiling tool then feeds the spiral wire through the perforations, and the ends of the spiral are cut and bent inwardly. The clamps are then separated and the book removed.
2. Description of the Prior Art
In conventional coil binding machines of this type the rear clamp is fixed and the front clamp swings, the facing surfaces of the clamps being vertical. While the clamps are adjustable axially there is no provision in prior machines for preselecting the height or the angle at which the unbound book is inserted by the operator into position for clamping. The normal arrangement is such that the operator must be in a sitting position for insertion between the vertical faces of the clamps. It is known to have coil binding machines of this type with clamp faces horizontally disposed. Here again, however, the clamps are fixed and no adjustment in height or angle of book insertion is possible.
An industrial user of such machines will typically have orders for various sizes of books in terms of length and thickness. In some instances it is desirable that the operator stand when inserting the books for binding. This is true for example when relatively long sheet groups are involved such as large calendars. Also, in some instances the coil binding machine is placed next to a hole punching machine in which case it is more convenient for the operator to be in a standing position when receiving sheet groups from the punching machine to be placed in the binding machine. To do this, the clamps should be relatively high with their facing surfaces horizontal. For thick books however a horizontal position is unsatisfactory since it is necessary to hang such thick sheet groups on curved hooks in order to shape the holes for receiving the spiral wire. This would require clamp faces in a vertical position.